Seven teams made head coaching changes after last season and the vast majority of teams around the league have made offensive or defensive coordinator changes. Here is a quick look at some of those staff moves in the AFC.

BUFFALO BILLS: Sean McDermott had a successful first season in Buffalo with nine wins and a playoff berth. Expectations for year two are identical to last summer however. There are big changes on the roster and on the staff with the big move of Brain Daboll replacing Rick Dennison as offensive coordinator. Daboll was Alabama's OC last season and has been an assistant with five NFL teams most notably with New England.

MIAMI DOLPHINS: Dowell Loggains in the new offensive coordinator for the Dolphins replacing Clyde Christensen who will remain with the team in a player development role. Loggains has been the OC with the Bears the past two seasons.

NEW ENGLAND PATRIOTS: Josh McDaniels was expected to leave the Patriots but will remain leading the offense. Matt Patricia is now the head coach in Detroit and Bill Belichick did not officially hire a new defensive coordinator. Linebackers coach Brian Flores who has been an assistant with the team since 2004 will get added responsibility with play calling duties but has not been given the DC label.

NEW YORK JETS: John Morton was fired after one season as the offensive coordinator. Last season's QB coach Jeremy Bates was promoted to the OC role for 2018, the sixth person in that position over the past eight seasons for the Jets. Bates was the OC for the Seahawks in 2010. Heading into his fourth season only four of the original 18 assistants under Todd Bowles remain with the team.

BALTIMORE RAVENS: Dean Pees resigned as defensive coordinator and is taking over that role in Tennessee. Don Martindale who has been the linebackers coach with the team since 2010 was promoted to the DC role for 2018. Martindale was previously the DC for the Patriots from 2006-2009.

CINCINNATI BENGALS: Most of last season it was expected that Bengals would have a new head coach this season but a change of course has Marvin Lewis still leading the team. A change at defensive coordinator did occur with Paul Guenther out after four seasons (and now in that role with Oakland) while Teryl Austin takes over that role after serving as the DC for the Lions the past four seasons. Bill Lazor took over the OC position last September and was retained.

CLEVELAND BROWNS: Former Chiefs head coach and Steelers offensive coordinator Todd Haley jumps within the division to lead the Browns as the new OC for 2018 after six seasons in Pittsburgh. Head coach Hue Jackson has been the offensive play caller the past two seasons with no one on the staff with an OC title. Haley will now take over the play calling role with former Bengals OC Ken Zampese now the QB coach in Cleveland.

PITTSBURGH STEELERS: Randy Fichtner has been a Pittsburgh assistant since 2007 and he will maintain his QB coach role while being the new OC in 2018.

HOUSTON TEXANS: Mike Vrabel left to take over the Titans while Romeo Crennel slides back to the defensive coordinator role where he served with the Texans from 2014-16 before being assistant head coach last season, a role he still also holds.

INDIANAPOLIS COLTS: The Colts overhauled the staff with former Eagles OC Frank Reich the new head coach. Reich didn't call plays in Philadelphia which he intends to do in Indianapolis but he has been an assistant in around the league starting in Indianapolis in 2008. Nick Sirianni is a first time OC after being an assistant with the Chiefs and Chargers the last decade. Matt Eberflus is the DC as a Dallas assistant in recent years.

JACKSONVILLE JAGUARS: Doug Marrone was able to keep his staff mostly in tact with neither coordinator departing despite a great rise for the team last season. As one of the few teams without a new coordinator the Jaguars should have optimism for 2018.

TENNESSEE TITANS: The Titans have won nine games the past two seasons including a playoff win last season but a new staff takes over with Mike Vrabel the new head coach after just one season as DC in Houston and only four seasons as a NFL assistant. Matt LaFleur led the Rams to the most point in the NFL last season in his only season as OC and he takes over that role with the Titans. Former Patriots and Ravens DC Dean Pees will lead the Tennessee defense after a very brief retirement. Pees will be 69 when the season starts.

DENVER BRONCOS: Six assistants were fired after the 2017 season but both coordinators remain for the Broncos with Joe Woods OC and Bill Musgrave DC under Vance Joseph. Woods took over for Mike McCoy last November.

KANSAS CITY CHIEFS: Matt Nagy and Brad Childress depart the offensive staff and long-time assistant Eric Bieniemy will be the new OC for the Chiefs, last serving in that role at Colorado in 2011-12 and tasked with leading the offense under 2017 draft pick Patrick Mahomes III.

LOS ANGELES CHARGERS: The Chargers retain both former head coaches Ken Whisenhunt and Gus Bradley as the 2018 coordinators under head coach Anthony Lynn. This team has perhaps the least staff turnover in the league following last season's 9-7 debut for Lynn and the move to the greater Los Angeles area.

OAKLAND RAIDERS: Jack Del Rio was fired after a disappointing second season with the Raiders with former Raiders and Buccaneers head coach Jon Gruden taking over. Paul Guenther is the defensive coordinator after serving in that capacity for the Bengals the past four seasons. Well traveled assistant Greg Olson will be the OC, previously in role in Oakland in 2013-14 as well as in stops in Detroit, St. Louis, Tampa Bay, and Jacksonville before working with the Rams as QB coach last season and bringing the arrival of Jared Goff. The Raiders are one of the few teams with the same projected QB rotation as last season.